The invention relates to a tester for testing a tilt angle of a seatbelt retractor to be manufactured in various sizes, and particularly, to a control system of a tilt angle tester including at least one sensor and a locking device cooperating therewith and for enabling the tester to check the operating performance of a seatbelt retractor to be mounted in a slant state on a seat frame of a vehicle in general and a method therefor.
Generally, a seatbelt retractor is a kind of a safety apparatus for protecting a driver or passenger who wears a seatbelt in a vehicle in a manner to fasten the driver to a seat in an accident such as rapid acceleration or deceleration, crashing, etc., thereby preventing a serious wound due to the clashing against the vehicle structure or the escape out of the vehicle. In other words, the seatbelt is drawn out of the retractor in a normal state of the vehicle, but its pulling-out is hindered in an emergency or abnormal state of the vehicle, especially excessive slanted state of the vehicle, because the retractor is provided with a web sensor and a vehicle sensor mounted therein. The web sensor and vehicle sensor are supposed to detect the abnormal state of the vehicle on time in order to prevent the pulling-out of the seatbelt. The web sensor functions to detect the pulling-out acceleration of the seatbelt, and the vehicle sensor acts to detect the abnormal state of the vehicle due to the crashing accident. So, it prevents the pulling-out of the seatbelt at over predetermined rapid acceleration or below predetermined rapid deceleration along or cooperating with the web sensor. These sensors may not allow the driver or passenger to wear the seatbelt if the vehicle is under the abnormal state. Also, the pulling-out of the seatbelt put on by the driver may be prevented. Herein, it is noted that in order to secure the normal operating of the seatbelt retractor to be mounted in the vehicle, it is important to check the operating performance of the web sensor and the vehicle sensor according to the tilt angle of the seatbelt retractor as well as to check the function state of the seatbelt pulling-out, exactly. It is very critical to the performance of the seatbelt retractor.
A typical conventional technology is disclosed in U.S. Pat. No. 4,630,472 entitled xe2x80x9cSeatbelt Test Apparatusxe2x80x9d. The patent adapts a system of testing the operating state of a seatbelt retractor in a manner that the seatbelt is pulled out by a power motor according to the change of the tilt angle of the retractor under the condition that it is completely wound around a bobbin of the retractor, after the seatbelt and retractor are mounted at a state similar to that mounted in a vehicle.
But, the patent has a disadvantage in that it is hard to evaluate the inherent operating relationship of the retractor, because the seatbelt has its own inherent tension taking bad effect on the seatbelt along with another factor in the vehicle. Also, the seatbelt may be arranged at a different position according to a kind of the vehicle, so the retractor has a different title angle corresponding to a kind of a vehicle to be mounted. Then, the retractor seems like to be differently operated at every place to be mounted in the vehicle. The patent has a difficulty in specifying the exact operation relationship of the retractor with a locking device that is operated by at least one sensor provided therein because of the restriction of the tilt angle to be tested.
An object of the invention is to provide a control system of a tilt angle tester for a seatbelt retractor for enabling a performance test of the seatbelt retractor associating with a locking device according to a PLC control method with respect to a relative wider tilt angle, in which the retractor comprises at least one sensor and the locking device cooperating with the sensor and a control method therefor.
Another object of the invention is to provide a control system of a tilt angle tester for a seatbelt retractor for controlling a title angle tester to judge whether the seatbelt is pulled out or drawn out according to an auxiliary angle of the retractor to be mounted under the state being not wound around on the retractor, thereby enabling the exact evaluation on the operating relationship of the retractor cooperated with a locking device without being the influence of the webbing.
Another object of the invention is to provide a control system of a tilt angle tester for a seatbelt retractor and for controlling the tilt angle tester to judge whether the seatbelt is drawn or pulled out, adapting an auxiliary tilt angle to be freely changed to the retractor with a seatbelt being not wound thereon and a control method therefor.
According to the invention, a control system of a tilt angle tester for a seatbelt retractor comprises a motor control portion connected to a PLC (Programmable Logic Controller) to control the rotation of motors at a tilt angle to be inputted in advance; a rotary cylinder control portion for controlling the rotating of a rotary cylinder in order to rotate a spool of the retractor; a stamping control portion for controlling the operating timing of a stamping portion; a memory for enabling various control operations of the PLC; registers for storing digital data code values corresponding to a plurality of tilt angles thereat; and a multi-axis motion controller for calculating or computing the digital data values, therefore enabling the tilt angle of the seat belt retractor to be tested with a holder structure being slanted.
A control method of a tilt angle tester for a seatbelt retractor comprises steps of turning on a starting switch after the seatbelt retractor is mounted in a holder structure; judging whether a basic value is set corresponding to a tilt angle to be inputted; fetching data of a digital code corresponding to the tilt angle; rotating at least one motor to correspond to a data value; rotating a spool of the seatbelt retractor by means of a rotating portion of a rotary cylinder; stopping the applying of an air pressure to the rotary cylinder before the 0.5 second of a system delay time at the time of the rotary cylinder being operated; and judging whether a web sensor and a vehicle sensor are in a good condition or not.
A control system of a tilt angle test apparatus for a seatbelt retractor comprises a motor control portion connected to a PLC to test the retractor mounted on a holder structure and to control the rotating of servo and step motors at a tilt angle to be inputted; a rotary cylinder control portion for controlling the rotating of a rotary cylinder so that a spool of the retractor is rotated; a stamping control portion for controlling the operating timing of a stamping portion; a memory for storing data values necessary for various control operating of the PLC, previously; a data register for storing digital code data values corresponding to the tilt angles; and a multi-axle operating controller for computing the digital code data values.
A control method of a tilt angle test apparatus for a seatbelt retractor comprises steps of turning on a starting switch after the retractor is mounted on a holder structure; judging whether a basic value corresponding to the tilt angle inputted is set; judging whether digital code corresponding to the tilt angle is set; fetching a data value at a digital code corresponding to the data value; rotating a spool of the retractor by a rotating portion of a rotary cylinder; stopping the supply of an air pressure before an inner delay time of 0.5 sec upon the operating of the rotary cylinder; and judging whether web and vehicle sensors of the vehicle are good or not and determining the state of the retractor.